This invention relates to a hold-down device for restraining vertical movement of an article away from a supporting platform, and particularly to restrain a heavy battery to the supporting platform of a vehicle.
In many electrically actuated and electrically driven vehicles it is the practice to mount the battery unit within a shallow pan which only restrains horizontal movement thereof. The assumption is made that the heavy weight of the battery is sufficient to hold it within the edges disposed around the periphery of the pan. While this contributes to the ease of serviceability of the battery unit the battery could be dislodged from its position.
The above-mentioned deficiency has been recognized heretofore, and this has resulted in the development of a number of more positive clamping devices which have been utilized to secure a battery unit vertically to the pan. These devices are exemplified by the following U.S. Pat. Nos.:
3,254,736 issued June 7, 1966 to H. A. Goss PA1 3,333,810 issued Aug. 1, 1967 to W. J. Schlapman PA1 3,557,895 issued Jan. 26, 1971 to F. W. Thomas PA1 3,581,837 issued June 1, 1971 to J. H. Bauschard.
Unfortunately, these and other known hold-down devices are not conveniently adjustable and are often excessively complex and costly in construction. For example, threaded bolt and nut clamping devices require a wrench and an extended service period for a mechanic to screw threadably tighten the retaining nuts securely in place. Other constructions are too bulky or are simply not sturdy enough to positively retain the full weight of a heavy battery unit.